Adaptive Control of Hydraulic Shift Actuation in an Automatic Transmission by Sarah Marie Thornton B.S. Mechanical Engineering University of California at Berkeley, 2011ARCHVES MASSACHUSETTS INSTI E OF TECHNOLOGY JUN 2 5 2013 L BF3RAR IE S Submitted to the Department of Mechanical Engineering in partial fulfillment of the requirements for the degree of Master of Science in Mechanical Engineering at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June 2013 © Massachusetts Institute of Technology 2013. All rights reserved. A u th or .............................................................. Department of Mechanical Engineering May 10, 2013 Certified by............. .......................... . Dr. Anuradha Annaswamy Senior Research Scientist Thesis Supervisor Accepted by....................... .......................... David E. Hardt Chairman, Department Committee on Graduate Students 2 Adaptive Control of Hydraulic Shift Actuation in an Automatic Transmission by Sarah Marie Thornton Submitted to the Department of Mechanical Engineering on May 10, 2013, in partial fulfillment of the requirements for the degree of Master of Science in Mechanical Engineering Abstract A low-order dynamic model of a clutch for hydraulic control in an automatic trans- mission is developed by separating dynamics of the shift into four regions based on clutch piston position. The first three regions of the shift are captured by a physics- based model and the fourth region is represented by a system identification model. These models are determined using nominal values and validated against nominal and off-nominal experimental data. The model provides two lumped flow parameters to be used for tuning to the desired hydraulic clutch system. Using feedback information from the model and transmission mechanicals, a closed -loop adaptive controller is designed. The controller is structured to update at three different rates: every time instance, every shift, and every n-th number of shifts. Part of the controller is designed to operate in open-loop for the first two regions of the shift until feedback information is available. The open-loop controller adapts within the shift, thus allowing for corrections to the control design to be made in following shifts. The model tuning parameters as well as the main spring preload become the adaptive parameters, which are then adjusted so that the plant matches the model. The control design is validated against a high fidelity simulation model of the transmission hydraulics and mechanicals. Thesis Supervisor: Dr. Anuradha Annaswamy Title: Senior Research Scientist 3 Acknowledgments Dr. Annaswamy, thank you for the opportunity to work with you on this project. Your guidance and expertise have taught me many new skills as a researcher. To my colleagues at the Ford Motor Company: Thank you Diana Yanakiev for your mentorship and knowledge throughout this project. It has been a real pleasure working alongside you, thus allowing me to gain confidence in my abilities as a researcher. Thank you Greg Pietron for your major contribution in developing the model of the hydraulic clutch actuation. Also, thank you for always critizing my data visualizations, thus teaching me the importance of proper graphical communication. In addition, thank you for allowing me and Diana to continually bother you with our questions about the complicated behavior of the transmission. Thank you James McCallum for your high fidelity transmission simulation model as well as for your quiet tolerance of our many meetings. Lastly, thank you to Joseph Kucharski for your help in gathering vehicle data. I would like to thank all my friends at MIT for the study groups and many posi- tive memories. My time here would not have been the same without you all to share it with. I would especially like to thank my husband, Joseph, for his sacrifice and patience while his wife travelled to the otherside of the country in pursuance of this experience. I would not have